1. Field of the Invention
Inkjet printing apparatus or inkjet printers are already known, in which an ink tank or ink reservoir is placed in front of a nozzle or a group of nozzles of a printing head for applying or discharging inks. The ink reservoir is connected via channels to the nozzle or group of nozzles on the one hand and via a feed line to the ink tank on the other hand. The disadvantage of this was that due to this method of supplying ink printing devices could only be produced that could handle one type of ink. In order to work with different types of ink the machine needed to be completely reset.
2. The Prior Art
The demand for inkjet printers that use various different ink systems, i.e. inks of different kinds, is particularly high in large scale production, where the same printing apparatus needs to be used for printing different materials, such as paper, cardboard, plastic film or even textiles. Solutions to this problem have already been proposed which enable an inkjet printer to be reset to use different ink systems.
In U.S. Pat. No. 6,024,441 A an inkjet printing apparatus is described, comprising ink storing tanks, flexible feed lines and connecting units for the printing heads. For different colours from different ink systems feed lines run from the ink tanks to a connecting unit belonging to an ink system The printing heads of the inkjet printing apparatus are in turn connected to printing head connecting portions on the printing head connecting units, whereby the supply of ink to the printing heads is ensured. In order to reset the inkjet printing apparatus to a new ink system it is necessary to remove the printing heads from the inkjet printing apparatus by releasing the printing head connecting portions from the printing head connecting units. The printing heads are then exchanged and the new set of printing heads are connected to the printing head connecting units of the new ink system. The exchange of the ink system in inkjet printing apparatus as described in U.S. Pat. No. 6,024,441 A thus requires a considerable amount of manipulation to remove or install the printing heads.
The objective of the present invention is to create an inkjet printing apparatus which can be used universally without the need for long resetting times at the inkjet printer.